US President George W Bush has cut short his holiday and returned to Washington to co-ordinate the relief effort following Hurricane Katrina.

He is expected to tour the southern states affected later in the week.

The president has already ordered oil to be released from the US strategic reserve in order that oil prices can be stabilised.

Mr Bush's plane, Air Force One, dipped low over New Orleans as he travelled back from Texas to the White House.

Mr Bush was getting a view of the extent of the damage - but he was also sending an important signal to those who saw the unmistakable plane from the ground and for those who saw it on television.

The message: the White House is on the case. The president is no longer on holiday, he is engaged 100%.

Extra muscle

For Mr Bush, the events of the last few days provide both problems and opportunities.

The initial problem is coping with the immense scope of the disaster.

The president had an aerial view of the devastated region

On Wednesday evening, the president chaired a meeting of the White House task force set up to co-ordinate the relief effort. That effort will need to be speeded up and given extra muscle.

The American people do not expect miracles of their presidents - but they do expect a leader who spends considerable resources on foreign adventures to be able and willing to do the same at home.

There is at least one unit of the Louisiana National Guard on duty at the moment in Iraq.

Mr Bush will be keen to avoid accusations that the relief effort has been delayed or weakened by other commitments.

To that end the resources of the US Navy are being tapped. Four Navy ships have steamed out of their port at Norfolk, Virginia, and a hospital ship is also on its way to the Gulf Coast.

Coping with disaster

In the longer term, the president has an opportunity to build a second term legacy based in part on a successful reaction to a natural disaster.

His opinion poll ratings are currently at record lows, with the latest Washington Post-ABC survey putting his approval rating at 45%, down seven points since January.

Anything which takes Iraq off the news here, and which focuses minds and resources on other issues, can only do the president good - provided that he is seen to be coping well.

And to put it mildly, there is plenty to be coped with.

Experts have been making it clear - in case anyone has failed to realise so far - that this is a long-term disaster, with problems of disease, poverty and trauma which will last for months, if not years, to come.

Local officials are talking of months before there is any proper clear-up in some regions, months before there are any basic services.

How the president sorts out the mess - his tone and the substance of his contribution - will be noted by all Americans.